چكيده به لاتين
Abstract.UWB antennas with high data rate are very popular. From UWB antennas to spiral
antenna, Logperiodic, dual cone, dual triangle, horn and Vivaldi antenna, each of which has
advantages and disadvantages. There are problem such as Complex structure, phases center
instability, large antenna dimensions that are necessary for better performance of this type of
antenna. The main advantage of Vivaldi antenna is its simple structure compared to other UWB
antennas. Also, medium gain, wide bandwidth, high directivity, endfire beam, almost stable
radiation pattern and the possibility of antenna minimization are other features of this antenna.
It is applications such as ground penetrating radar (GPR), microwave imaging, short-range
communication. The passage of a wave through a narrowing aperture along the axial line of the
slot line is the main cause of radiation in the Vivaldi antenna.However, the antenna gain is low in
the low frequency band and the antenna beam is small in the high frequency band. techniques
is presented for the radiation performance improvement including corrugation,Array Vivaldi
antenna , cross-shaped structure dual polarization Vivaldi antenna and the use of director
including grating elements, parasitic patches, metamaterial, lens and dielectric part come
forward or are provided with different dielectric constants. In this work, the structural correction
is done by using corrugation, the gain is amplified in all frequency ranges, especially in low
frequency band, and also by using the grating elements of the beam consolidation and
strengthening in the direction of the endfire, the coplanar Vivaldi antenna on the band Frequency
2-12GHz is provided with a new improved design. We have increased the bandwidth in the low
frequency band by almost 100MHz and with improved gain in the whole frequency range and the
increase in gain up to 1db in some parts.
